Reinvestigation of the level structures of the even-even nuclei Zr90 and Zr92

Excited states of 90Zr and 92Zr were investigated using the fusion reactions Li6+Y89 and N14+Se82, respectively. Based on the experimental data, 5 and 18 new γ rays have been added to the level schemes of Zr90 and Zr92, respectively. The level structures of Zr90 and Zr92 have been interpreted with shell-model calculations using the GWBXG and SNET effective interactions. The neutron core-breaking and the importance of the 1g7/2 and 1h11/2 orbits for high-spin states of Zr92 were discussed. The excitation energy of the neutron core-breaking of nuclei in the A=90 region was compared.